NEW: Predicting Developmental Disabilities in Infants: Using Electrophysiology 3/2006 

SUMMARY:
In February 2006, The UCP Research and Educational Foundation reviewed advances in brain imaging techniques that may lead to very early detection of brain abnormalities in infants. Early detection is important for prognosis and for providing opportunities for early interventions to improve the chances of better outcomes in children at risk. As mentioned in last month’s document: What research is being carried out to improve the early prediction of later disabilities in the highest risk newborns?, caution must be exercised, because brain image is not destiny, and until the relationships between apparently abnormal magnetic resonance imaging and later developmental delays have been established it is unwise to label children and limit expectations.

This month a discussion of another kind of early testing of the nervous system will be discussed. Electrophysiological tests of transmission of sounds presented to the ears, traveling through brain auditory pathways, and cortical responses (measured by EEG like electrodes) can give a great deal of information about the infant’s nervous system. Neuroscientists, physiologists, neurologists and pediatricians are experimenting with these tests, and many now contend that they can predict in infancy whether a child will later develop deficits in speaking, reading, memory, interpersonal relationships and bonding. Scientists can measure a great deal about function in the brains of infants—long before they can truly communicate with others. The work is predicated upon assumption that auditory processing speed and memory are critical infrastructure upon which to build intellectual and social learning and development. If the foundation is faulty, deficits will be apparent later on. If detecting the faulty foundation early is useful for prognosis and ultimately for therapeutic intervention trials, this work is indeed important.

Dr. Rose¹ and colleagues at the Albert Einstein College of Medicine in New York, recently published a study in the Medical Journal: Child Development.

This study examined the relation of information processing in 7-month-old preterms (<1750 g at birth) and full-terms to Bayley Mental Development Indexes (MDIs) at 2 and 3 years. The infant measures were drawn from four cognitive domains: attention, speed, memory, and representational competence. Structural equation modeling showed that these measures of infant information processing mediated the effects of prematurity, and that there was a cascade of effects, with infant processing speed influencing memory and representational competence, which in turn influenced later MDI. This study shows that infant information processing mediates the effect of prematurity on later cognition, and delineates pathways whereby infant abilities relate to one another and to later outcome.

Conclusions:
These researchers conclude that specific deficits in attention, speed, and memory can be detected within the first year of life, using these laboratory techniques. These laboratory measurements may provide a necessary piece of evidence to the clinicians and caregivers of these children.

Whether early detection correlates with substantial limitations in learning and societal function remains to be seen. Once established, the question that will further beg investigation is whether specific interventions geared toward practicing auditory functions, memory and social interactions can improve learning capacity and achievement at later ages. In addition, the testing of medications that enhance processing rates and attention span may be of value in enhancing mental development for infants with abnormal brain functions established by these methods